Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
  • B01D29/11—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with bag, cage, hose, tube, sleeve or like filtering elements
  • B01D29/13—Supported filter elements
  • B01D29/15—Supported filter elements arranged for inward flow filtration
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
  • B01D29/44—Edge filtering elements, i.e. using contiguous impervious surfaces
  • B01D29/48—Edge filtering elements, i.e. using contiguous impervious surfaces of spirally or helically wound bodies
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
  • B01D29/50—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with multiple filtering elements, characterised by their mutual disposition
  • B01D29/52—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with multiple filtering elements, characterised by their mutual disposition in parallel connection
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
  • B01D29/62—Regenerating the filter material in the filter
  • B01D29/66—Regenerating the filter material in the filter by flushing, e.g. counter-current air-bumps
  • B01D29/668—Regenerating the filter material in the filter by flushing, e.g. counter-current air-bumps with valves, e.g. rotating valves for coaxially placed filtering elements
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2201/00—Details relating to filtering apparatus
  • B01D2201/02—Filtering elements having a conical form
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2201/00—Details relating to filtering apparatus
  • B01D2201/04—Supports for the filtering elements
  • B01D2201/043—Filter tubes connected to plates
  • B01D2201/0453—Filter tubes connected to plates positioned between at least two plates

Definitions

• the invention relates to a backwash filter device for the use of split screen filter elements which can be accommodated in a housing with a filter inlet and an outlet for the fluid to be filtered, the filter elements for filtration or backwashing can be flowed through in both directions and with a backwashing drivable flush arm is provided, which has a fluid outlet for contaminated fluid and which can be moved in succession under the passage cross-sections of the filter elements.
• Such a generic backwashing device is known from DE 40 30 084 A1.
• the known backwashing device which can be backwashed with the dirty liquid to be filtered, preferably in countercurrent to the filtering direction, it has a multiplicity of filter cells in a circular arrangement in the filter housing, which, with the aid of a flushing arm driven by a rotary drive, individually or in small groups for backwashing can be connected to the sludge drain.
• the dirty liquid passes through the filter cells in the longitudinal direction at high turbulent speed. flows and thereby loosens and removes the deposited contaminants, the filtering and backwashing results can be improved.
• the cylindrical filter elements in the known solution are arranged close to each other in the filter housing, the free outflow space in the filter housing is correspondingly small, so that in normal filtering operation, due to the mutual influence of the cylindrical filter elements, the outflow resistance for the filtered fluid is increased, and consequently also the pressure difference between filter inlet and outlet.
• this leads to an overall poor energy balance for the known arrangement described.
• a non-uniform liquid flow occurs, with the result that the fluid velocity within the cylindrical elements increases continuously, which also has an unfavorable effect on the energy balance of the entire backwashing device.
• DE 38 1 2 872 A1 discloses a conical filter element which is used for filtering and separating different substances and particles, a conically wound wire in the form of a spiral or a helical cone being guided within supporting rods which converge towards one another.
• the compact conical design in which the length-width ratio is in the range of 1, creates a kind of funnel effect that is intended to increase the separation efficiency.
• the conical filter and separating element in question were used in a backwashing device, no larger outlet cross section for the fluid compared to the inlet cross section formed by the filter surface would be achieved in this way, and thus increased flow resistances occur, which in particular impair the efficiency during backwashing.
• the invention has for its object to provide a backwashing device with improved filtering and backwashing performance and improved energy balance when the fluid flows through the respective filter element.
• a corresponding object is achieved by a backwash filter device with the features of claim 1.
• the conical slotted tube filter element has a clear advantage over a cylindrical one.
• the main reason for this is the relatively larger outlet cross-section of the conical filter elements compared to cylindrical ones with the same filter surface.
• the outlet cross-section of the conical filter elements is relatively small compared to the inlet cross-section formed by the filter surface, i.e. the free element surface, depending on the size of the flow resistance of the can, a bottleneck is formed in which a large part of the system pressure drops. There are therefore lower pressure losses, which is more economical when backwashing.
• the flushing arm in each case lingering a few seconds below the filter element at its passage cross section.
• the backwash valve opens quickly, creating a pressure pulse in the opening of the can, which also removes stubborn dirt.
• Fig.1 a in a partially cut form a side view of the
• FIG. 1b shows a section along the line II in Fig. 1 a; Fig. 1 c in an enlarged view a designated in Fig. 1 a with "X"
• FIG. 2 shows a longitudinal section through a backwash filter device with cylindrical and tapered wedge wire filter elements.
• the slotted sieve tube filter element 8 shown in a side view in FIG. 1 a has support rods 12 inclined towards it in the direction of its longitudinal axis 10, around which a wire profile 16 is wound in individual turns 18, leaving gaps 14 that are passable by a fluid, in the region a welding point is arranged at each point of contact of the wire profile 16 with the support rod 12.
• the gap size provided for the free passage of fluid, that is to say the distance between two columns 14, is shown in FIG. 1 c with arrows 20 facing one another.
• the respective support rod 12 is inclined with its one end 22 towards the longitudinal axis 10 in such a way that an overall conically tapering filter element 8 is formed, the windings 1 8 of the wire profile 16 thereby having a diameter in the direction reduce the inclined ends 22 of the support rods 12, which also results from the illustration according to FIG. 1 b.
• a plurality of wire profiles arranged one behind the other or wire profiles arranged and wound one above the other can optionally be used, provided this is necessary for the specified filtration task.
• the length L of the slotted screen filter element 8 measured in the direction of the longitudinal axis 10 is approx. 11 times greater than the largest available Passage cross section D for the fluid at the right end of the filter element 8 as seen in the direction of the Fig.la.
• the support rods 12 and the wire profile 16 are made of stainless steel, the support rods 12 being square in cross section and the wire profile 16 being triangular.
• the gap widths to be selected which are marked with a double arrow 20 in FIG. 1 c, are to be adapted to the size of the solid parts to be filtered out of the fluid, in particular in the form of hydraulic oil, the filtered fluid freely passing through the columns 14 and the filtered off Solid or dirt parts retained by the windings 18 of the wire profile 1 6 remain within the filter element 8 or partially become stuck in the gaps 14, with the result that as the service life of the slotted sieve tube fiiter element 8 increases, this becomes increasingly clogged and not for carrying out a filtration can be used more.
• the filter element 8 is to be cleaned by backwashing in the reverse direction of fluid passage.
• Fig.l a in principle, the direction of filtration from the inside to the outside is marked with an arrow 24 and the opposite backwashing direction with an arrow 26.
• the backwash filter device shown in FIG. 2 has a cylindrical housing 30 with end covers 32, 34 which can be fixed to the filter housing 30 via flange connections 36.
• the housing 10 of the backwash filter device has a filter inlet 38 for the fluid to be filtered and a filter outlet 40 for the filtered fluid.
• the fluid direction in the filtering operation through the housing 30 is indicated in FIG. 2 with corresponding arrows at the filter inlet 38 and filter outlet 40.
• cylindrical filter elements 42 are also used. Both the conical slotted-tube filter elements 8 and the cylindrical slotted-tube filter elements 42 are divided into groups and spaced from one another multiple times along cylindrical arcs within the filter housing 30. All filter elements shown in FIG.
• a drivable flushing arm 50 is provided, which on its underside provides a connection in the form of a fluid outlet 52 for contaminated fluid.
• the flushing arm 50 which has two different arm sections 54 in length, can be moved in succession via a drive linkage 56 under the passage cross sections D of the conical and cylindrical filter elements 8 and 42.
• the backwashing is therefore carried out continuously with the actual filtration process, only the filter elements 8, 42 being backwashed, from the outside inwards, with the cleaned, filtered fluid produced during the filtration with the other filter elements, the free passage cross sections D of the arm sections 54 of the rinse arm are 50 grips.
• the direction of exit of the fluid so contaminated and formed during backwashing is shown in FIG. 2 with an arrow at the fluid outlet 52.
• the drive linkage 56 extends through the filter housing 30 along the longitudinal axis 58 of the backwash filter device and extends through both the upper end cover 32 and the lower end cover 34.
• drive linkage 56 in particular in the form of a hollow shaft, a spline connection 60 is provided on the upper end cover 32, through which the drive linkage with a motor or the like. can drive for a rotating revolution about the longitudinal axis 56.
• the filter inlet 38 is constructed from its wall in the manner of a diffuser, which reduces the fluid entry speed of the contaminated fluid to be filtered, while at the same time increasing the pressure on the passage cross sections D of the conical and cylindrical passages exposed by the flushing arm 50 Filter elements 8 and 42.
• the diffuser effect is particularly favored by the fact that the inlet cross-sections at filter inlet 38 and the cross-section of the receiving space for filter elements 8 and 42 are essentially the same and the transition between filter inlet 38 and receiving space is essentially uniform without Cross-section is reduced.
• the conical structure of the slotted tube filter elements 8 ensures that the passage area D in the respective element is very large, the distance between the conical elements 8 and between them and the cylindrical elements 42 increasing in the direction of the filter outlet 40, so that the filtered fluid exits from the interior of the respective filter element, a smaller resistance is opposed to the conventional solutions with exclusively cylindrical elements, with the result that the ratio ⁇ p of the entire backwash filter device is reduced in terms of energy. Furthermore, due to the conical structure of the slotted-tube filter elements 8, a constant liquid flow is achieved when the elements are backwashed, whereas with cylindrical elements 42, which are also used in the present embodiment, the speed in the longitudinal direction of the same increases constantly in an energetically unfavorable manner.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Filtration Of Liquid (AREA)
• Extraction Or Liquid Replacement (AREA)
• Separation Using Semi-Permeable Membranes (AREA)
• Water Treatment By Sorption (AREA)
• Non-Reversible Transmitting Devices (AREA)
• Oscillators With Electromechanical Resonators (AREA)
• Diaphragms For Electromechanical Transducers (AREA)
• Encapsulation Of And Coatings For Semiconductor Or Solid State Devices (AREA)
• Separation By Low-Temperature Treatments (AREA)
• Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=7823992

Family Applications (1)

Country Status (8)

Families Citing this family (17)

Family Cites Families (5)

• 1997
  • 1997-03-20 DE DE19711589A patent/DE19711589A1/de not_active Withdrawn
• 1998
  • 1998-01-21 DK DK98907968T patent/DK0968039T3/da active
  • 1998-01-21 WO PCT/EP1998/000310 patent/WO1998042426A1/fr active IP Right Grant
  • 1998-01-21 JP JP54087998A patent/JP4065331B2/ja not_active Expired - Fee Related
  • 1998-01-21 ES ES98907968T patent/ES2186130T3/es not_active Expired - Lifetime
  • 1998-01-21 EP EP98907968A patent/EP0968039B1/fr not_active Expired - Lifetime
  • 1998-01-21 AT AT98907968T patent/ATE226105T1/de active
  • 1998-01-21 PT PT98907968T patent/PT968039E/pt unknown
  • 1998-01-21 DE DE59805969T patent/DE59805969D1/de not_active Expired - Lifetime

Non-Patent Citations (1)

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